Combination azimuth and bearing circle



Nov. 12, 1940.

w. NAECKER 2,220,945

COMBINATION AZVIMUTH AND BEARING CIRCLE Filed July 28, 1939 s sheets-sheet 1 INVENTOR WILL/AM NAECKER BY [4%. W

ATTOR' Nov. 12, 1940. w. NAECKER 2,220,945

COMBINATION AZIMUTH AND BEARING CIRCLE Filed ,July 28, 1939 s Sheets-Sheet 2 INVENTOR WILLIAM NflECKER BY ATTORN Nov. 12, 1940. w. NAECKER 2,220,945

COMBINATION AZIMUTH AND BEARING CIRCLE Fild July 28, 1939 3 Sheets-Sheet 3 FIG- 9;

I BIVENTOR WILL/AM NAECKER pal v yom ATTORNEY Patented Nov. 12, 1940 com mow PA ENTiomce BEARING William MQ H QSnau.in. Application July 28; 1939, serialno. 287,028

screams. (ones- 23) I Q .(Gr'anted'und er the act of March 3, 1883, as

amendedApril 30, 1928 3700. 757.)

This invention V relates to a combination azimuth and bearing circle intendedfor use with a magnetic compass or pelorus dial to take bearings and azimuths l l A further object of this invention is to provide an azimuth and bearing circle wherein the,

azimuth units and bined. i

A further object of this inventionis to provide a new type of circle so constructed that it will reduce the cost of upkeep and repair to a minimum in that it enables the following workto be performed aboard ship: i I

The azimuth bearing units can be checked and adjusted without'the aidof a collimator. Removable pivots and bushings are provided which act as bearings and are arranged so that the various vanes and mirrors can be replaced. -Adjustable ring pads are provided toexpedite the centering of the bearing ring.

A further object of this invention is to provide means for taking a more accurate azimuth as the the bearing units are comblack wire center line is reflected on the compass card or pelorus dial, accurately centering the reflected beam of light. i l v i .With the foregoing and other objects in view,

the invention consists in the construction, com

bination, and arrangement of'parts hereinafter described and illustrated in the drawings, in which y i Fig. lis a top plan view of the azimuth'and away of the means foradjusting the plane of the mirror;

Fig. 6 is an elevational view of the eccentric pivot for adjusting themirror;

. Fig. 7 is an elevational view of the concentric pivot; l

Fig. 8 is a perspective view of the prism cross wire frame;

Fig. 9 is a schematic diagram showing the taking of an azimuth;

Fig. 10 is a perspective and Fig. 11 is an enlarged perspective view of the mirror slit.

There is shown at l 0 the circle having the-usual degree markings II and provided with the usual downwardly extending flange I2 for locating the circle Ill on the bowl of the compass above the View of the ring pad;

compass card. Extending through the flange I2,

is a yieldable pad 13 mounted on aleaf spring 14. The spring 14 is secured to the outside of the flange [2 by means of a screw extending through a. hole l5-at one end of theleaf spring l4 and by a secondscrew extendingthroug h an elongatedslot 16 in the other end of the leaf spring 14, thereby permitting the spring I4 and the pad 13 to yield outwardly; Equi-distantly spacedfrom pad l3 about theflange 12 are two adjustable pins I1 threadedly adjustable through theflange l2 and secured in adjusted position -by means of lock nuts .I 8. By proper-ly adjusting the threaded pin H the circle II] can be perfectly centered on the top of the compass bowl.

In this invention the azimuth units and the bearing units are mounted on common supports. A supporting framework 2!] is attached to the circle [0 at the position by-a screw 2! extending therethrough. This framework 26 is somewhat U-shaped in outline, the bight 22 forming the base through which thescrew 21 extends, while upstanding legs 23 and 24 provide supports for the threaded bearing pivots25 and 25 for the slit mirror 21. The slit mirror 21 consists of a framework 28 having an opaque backing 30 secured thereto as by screws, which like wise extend through an opaque front members! provided with a centrally located vertical'ly extending longitudinal slit 32. p

Within the frame 28 and between' the back 30 and front 3| is a cylindric'ally curved reflecting mirror 33. g an enlarged cylindrical flange 34 having its ends conically recessed to receive the bearing points 35 and 36 of the threaded bearing pivots 25 and 26. The conical bearing point 35 of bearing pivot 25 is eccentrically located as shown in Figs.f5 and 6, while the bearing point 36 of the bearing pivot 261 is concentrically located, as-shown in Figs. Band "7. By proper manipulation of these bearing pivots 24 and 25 it is obvious that the plane of a tangent to the cylindrical mirror 33 in framework28 can be adjusted as brought out in Fig. 5, until it is in a plane exactly parallel to a tangent to the circle l0 atthe 180 mark, as desired. When fixed in this proper parallel positibn locking set screws 31 extending downwardly The mirror frame 28 is provided with l through the top of the legs 23 and 24 may be tightened against the sides of the pivots. 25 and 26 to keep them in adjusted position."

Secured to the bight 22 of the framework 20.

position of the supporting framework 20 at the 360 position is another framework 42 secured to the circle ID by means of screws 43 projecting through the extended base 44. The framework 42 includes a prism housing 45 extending upwardly from the base 44 for supporting the prism 46. The prism 46 has a front vertical face and a bottom horizontal face 48. A bubble level 50 is supported directly beneath the vertical prism face 41 by means of a plate 5| extending across the sides of the prism housing 45. A second plate 52 is secured across the top of the prism housing 45 as by screws 53 and is provided with a pair of upstanding legs 54 between which are pivotally mounted the cross wire front sight frame 55 and the black mirror frame 56. Mounted across the lower vertical prism face 48 is a lower plate 51 provided with a cross wire 58 extending centrally thereof, the frame 51 being provided with re-' 30 provided with screw kerfs 65. By rotating the bushings 64 by means of a screw driver in the kerfs 65 the bushings 64 may be moved transversely of the housing 45 tothus transversely adjust the position of the cross wire frame 55 35 and its cross wire 66 so that the cross wire 66 is exactly in the 0360 position, the cross wire 66 being secured on the frame 65 by means of screws 61. After the cross wire 66 has been brought to the exact position desired it may be held in such desired position by means of locking set screws 0 68 extending downwardly through the tops of the legs 54. The plane of the black mirror It! on the black mirror frame 56 may be adjusted so as to be exactly parallel to a tangent to the circle I0 at-the 0360 position by means of the same type of adjustable bearing pins 25 and 26 with the eccentric point 35 and a concentric bearing point 36. c j r The cross wire frame 55 is yieldably held inany position by means of a spring pressed stud 15 mounted on a boss I6 on plate 52 and pressing against the bottom of the cylindricalflange 62.

In operation, an azimuth may be taken in the manner diagrammatically illustrated in Fig. 9 where a ray of light II from the sun 11 is refiected throughthe slit32 by the mirror 33 through the front face 4! of the prism 46 down onto the compass card 72 at 13. The cross wire 58 splits the reflected beam 13 at 58* when the azimuth is correctly taken, enabling the azimuth c and location when the true azimuth is accurately known, and then adjusting the plane of the mir- -ror 33 until the azimuth taken thereby coincides with the known true azimuth, thus eliminating the necessity for returning the azimuth bearing circle to a shop on shore for making this correction. In the same way, the cross wire 66 may be transversely adjusted by checking it against the known bearing of aterrestrial object. Simiing from the nature of the invention, within the scope of what is hereinafter claimed.

The invention herein described and claimed may be used and/or manufactured by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor;

I claim: 7

1. In an azimuth bearing circle, an azimuth bearing unit support, a pivotally supported reflecting mirror, and means for adjusting the axis of rotation of said mirror on said support to make said axis of rotation parallel to a tangent to the circle at the point of support.

2. In an azimuth bearing circle, an azimuth bearing unit support, a pivotally supported refleeting mirror, means for adjusting the axis of rotation of said mirror on said support to make said axis of rotation parallel to a tangent to the circle at the point of support, said means comprising a pair of bearing pivots threaded in said support, a concentric bearing point on one of said bearing pivots, and an eccentric bearing point on the'other of said bearing pivots.

3. Inan azimuth bearing circle, an azimuth bearing support mounted on the circle, a vertical cross wire frame, means for transversely adjusting the position of said vertical cross wire frame on said support, said transversely adjusting means comprising a" bearing pivot, a pair of externally threaded bushings, said threaded bush ings extending transversely through said support, the ends of said bearing pivots extending into said bushings whereby said bushings may be adjusted in position to thereby adjust said vertical cross wire frame transversely.

\W ILLIAM NAECKER. 

